JPH0672909A - Production of tetracyclododecenes - Google Patents

Abstract

PURPOSE:To obtain the subject compound by reacting an alpha-olefin with cyclopentadiene or dicyclopentadiene and a norbornene in the presence of a specific high-boiling substance and to reuse a by-product as part of the raw material. CONSTITUTION:An alpha-olefin is reacted with cyclopentadiene(CPD) or dicyclopentadiene(DCPD) and a norbornene (RNB) or its hydrocarbon-substituted substance in the presence of a high-boiling substance having a higher boiling point than a tetracyclododecene to give the tetracyclododecene (RTD). In the reaction, a high-boiling substance prepared as a byproduct in the reaction is returned as it is to the reaction system and reused as part of the raw material. In the above-mentioned reactions, RNB is obtained by reaction between CPD and the alpha-olefin and RTD is obtained by reaction between CPD and RNB. Among high-boiling substances which are prepared as by-products by the reaction and are present in the reaction, tricyclopentadiene is thermally decomposed into CPD and DCPD, a Diels-Alder adduct (CPD/RTD) into CPD and RTD and DCPD is thermally decomposed into CPD.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing tetracyclododecenes. More specifically, it relates to a method for stably and efficiently producing tetracyclododecenes which are useful as raw materials for paints and polymers.

[0002]

Alkyltetracyclododecene, a compound useful as a raw material for paints and polymers, has been
By heating the olefin, cyclopentadiene or dicyclopentadiene, and norbornene,
It is manufactured by the Alder reaction (Diels-Alder reaction).

In Japanese Patent Publication No. 1-60011, 1 to 20 mol of olefin having 2 to 22 carbon atoms, 1 to 5 mol of cyclopentadiene or 0.5 to 2.5 of dicyclopentadiene.
Mol, and norbornene 1-5 mol, 100-40
0 ° C, 100-5,000 psi and 0.1-5 hours,
The mixture is heated and held in the reactor, and the product has a norbornene / tetracyclododecene molar ratio of 5/95 to 95 /
A method of making the mixture of 5 is disclosed.

In this method, for example, when ethylene is used as an olefin, a large amount of a high-boiling substance having a boiling point of tetracyclododecene or higher is produced as a by-product. This by-product of the high-boiling substance significantly reduces the yield of the target product, tetracyclododecene. However, in the production of tetracyclododecene, effective suppression of high boiling point substances has not been realized at present.

Further, in JP-A-3-128333, ethylene, cyclopentadiene or dicyclopentadiene, and norbornene are heated and reacted with an aromatic solvent, and the obtained reaction mixture is separated from a purification column. The reaction product containing tetracyclododecene is recovered from the bottom of the column and unreacted norbornene, cyclopentadiene or dicyclopentadiene, and the aromatic solvent are recovered from the top of the column to recycle tetracyclododecene. A manufacturing method is disclosed. However, this method does not describe reuse of a high boiling substance having a boiling point higher than that of tetracyclododecene as a raw material as a raw material.

Further, Japanese Patent Laid-Open No. 47-31964 discloses a process for producing alkenylnorbornene by the Diels-Alder reaction, in which a high boiling point by-product is thermally decomposed to obtain cyclopentadiene, which is cyclopentadiene or dipentane. A method of recovering cyclopentadiene for recycling is disclosed. This method includes a step of thermally decomposing a high-boiling substance produced as a by-product to recover cyclopentadiene or dicyclopentadiene as a raw material. In the example described in the publication, the same thermal decomposition step is carried out at 420 to 580 ° C.
It is disclosed that it was carried out in a high temperature electric furnace.

[0007]

An object of the present invention is to provide a method for efficiently producing tetracyclododecenes. Another object of the present invention is to provide a method for efficiently producing tetracyclododecenes by reusing the by-produced high boiling point substance as it is as a part of the raw material. Another object of the present invention is based on the discovery of the present inventor who found that the high boiling point substance produced as a by-product can be reused as a part of the raw material even if it is returned to the reaction system as it is, and it is excellent in economical efficiency. It is to provide a method for producing tetracyclododecenes. Yet another object and advantage of the present invention is
It will be apparent from the following description.

[0008]

According to the present invention, the above objects and advantages of the present invention include (a) an α-olefin,
(B) cyclopentadiene or dicyclopentadiene, and (c) norbornene or a hydrocarbon group-substituted product thereof are heated and reacted in the presence of a high-boiling substance having a boiling point higher than that of tetracyclododecene. A method for producing tetracyclododecenes, characterized in that the boiling point substance is separated and recovered from the reaction product obtained by the heating reaction of the components (a), (b) and (c). To be done.

The method for producing tetracyclododecenes according to the present invention will be described in detail below. Where α is appropriate
The olefin is 2 to 22 carbon atoms, preferably 2 to
Olefinic and / or aromatic olefins containing 12 and particularly preferably 2 to 8 carbon atoms. Representative examples of aliphatic α-olefins are ethylene, propylene, butene, etc., and examples of olefins having an aromatic group are styrene, etc.

In the method of the present invention, when an olefin, cyclopentadiene, norbornene or a hydrocarbon group-substituted product thereof is heated and reacted in the presence of a high-boiling substance,

(A) The following reaction (1) for producing norbornenes (RNB) by reacting cyclopentadiene (CPD) with an olefin.

[0012]

[Equation 1]

(Wherein R is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms or an aromatic group)

(B) The following reaction (2) for producing tetracyclododecenes (RTD) by the reaction of cyclopentadiene and norbornenes

[0015]

[Equation 2]

(C) The following reaction (3) in which, for example, tricyclopentadiene (TCPD) in a high-boiling substance is thermally decomposed into cyclopentadiene and dicyclopentadiene (DCPD)

[0017]

[Equation 3]

(D) Further, the following reaction in which a Diels-Alder adduct (CPD / RTD) of, for example, cyclopentadiene and tetracyclododecene in a high boiling point substance is thermally decomposed into cyclopentadiene and tetracyclododecene (4)

[0019]

[Equation 4]

The reaction of (2) proceeds.

In the method for producing tetracyclododecenes according to the present invention, when dicyclopentadiene is used instead of cyclopentadiene,

(E) The following thermal decomposition reaction from dicyclopentadiene to cyclopentadiene (5)

[0023]

[Equation 5]

Also proceeds at the same time.

Here, the reaction (A) and the reaction (B) are Diels-Alder reaction, and the reaction (C) and the reaction (D).
And the reaction (E) is a reverse Diels-Alder reaction.

In carrying out the reaction of the method of the present invention, cyclopentadiene exists as a dimer dicyclopentadiene at room temperature under normal pressure, and this dicyclopentadiene decomposes under the reaction conditions to give cyclopentadiene. In general, dicyclopentadiene is used in the reaction to produce At this time, unreacted norbornenes are recovered by distillation and recycled. Therefore, the change amount of norbornenes (ΔRNB) before and after the reaction is ΔR
It is preferable that NB = 0.

The high-boiling substance used in the present invention is
It is separated and collected as a component having a boiling point higher than the boiling point of tetracyclododecenes from the reaction products obtained by heating the components (a), (b) and (c). Such a high-boiling substance contains, for example, tricyclopentadiene or a Diels-Alder adduct of cyclopentadiene and tetracyclododecene as an active ingredient.

As the reaction apparatus used in the method for producing tetracyclododecenes according to the present invention, the apparatus generally used for producing alkyltetracyclododecene can be used as it is. A schematic diagram of a typical apparatus used in the present invention is shown in FIG. When producing tetracyclododecenes using such a reactor,
The dicyclopentadiene, the norbornenes, and the high-boiling substance supplied to the reaction system are mixed in a mixer at a predetermined ratio. This mixed solution is pressurized to 700 to 4,000 kPa by a compressor or pump and then mixed with α-olefin at a predetermined ratio. Mixture is 150-1
It is sent to a preheating chamber heated to 80 ° C., preheated to near the reaction temperature, and supplied to the reactor. In this case, the amount of the raw materials to be supplied is 1.5-6.0 mol of norbornenes, 0.4-2.0 mol of α-olefin, and all high-boiling substances are supplied per mol of dicyclopentadiene. It is preferably in the range of 1 to 35 parts by weight per 100 parts by weight of the raw material. In the method for producing tetracyclododecenes according to the present invention, the reaction temperature is 100 to 400 ° C., preferably 200 to 400 ° C.
300 ° C., pressure 700 to 40,000 kPa, preferably 3
000 to 30,000 kPa and a residence time of 0.1 to 5 hours.

Purification Step The mixture obtained by the reaction is sent to a post-treatment step, where it is cooled and depressurized, and then supplied to the first purification column. A mixture of unreacted norbornenes and a small amount of cyclopentadiene or dicyclopentadiene is recovered from the top of the column, and crude tetracyclododecene containing a high-boiling substance is recovered from the bottom of the column. A mixture of the recovered norbornenes and a small amount of cyclopentadiene or dicyclopentadiene is sent to the reservoir tank for storage so that the norbornenes do not solidify in the reservoir tank, and used again for the reaction. Crude tetracyclododecene containing high-boiling substances separated from the bottom of the column is sent to a refining tower, high-purity tetracyclododecenes are recovered from the top of the column, and high-boiling substances from the bottom of the column are recovered. Are collected respectively. The recovered high boiling point substance is sent to a reservoir tank for storage, and is used again in the reaction. The operating conditions in such a distillation column are as follows.
C, tower bottom pressure 15-75 kPa, tower top temperature 50-13
It is preferable that the temperature is 0 ° C. and the pressure at the top of the column is 13.3 to 70 kPa. In the second purification tower, the tower bottom temperature is 80 to 150.
C, tower bottom pressure 1.3 to 20 kPa, tower top temperature 60 to 13
It is preferable that the temperature is 0 ° C. and the pressure at the top of the tower is 0.13 to 12 kPa.

[0030]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

Example 1 A reaction was carried out using the apparatus shown in FIG. The reaction is ethylene, dicyclopentadiene, norbornene,
It was carried out by using a high-boiling substance having a boiling point higher than that of tetracyclododecene, which is a by-product during the production of tetracyclododecene. The weight ratio of these mixtures fed to the reactor was 5% by weight of ethylene, 20% by weight of dicyclopentadiene, 55% by weight of norbornene and 20% by weight of high-boiling substances. The reaction was carried out at a reaction pressure of 4600 kPa, a reaction temperature of 260 ° C. and a residence time of 20 minutes. The obtained mixture was processed in a post-treatment step and then sent to a purification step. At this time, the operating conditions of the refining process are as follows: in the first refining tower, the tower bottom temperature is 168 ° C., the tower bottom pressure is 16.6 kPa, the tower top temperature is 70 ° C., and the tower top pressure is 14.6 kPa. Tower bottom temperature 115 ° C, Tower bottom pressure 2.2
6 kPa, column top temperature 80 ° C., column top pressure 0.33 kPa.

The result is a cyclopentadiene conversion rate of 89 m.
It was ol% and the selectivity for tetracyclododecene was 84 mol%, and tetracyclododecene could be obtained in an extremely high yield.

Comparative Example 1 The reaction was carried out using ethylene, dicyclopentadiene and norbornene (all of which are the same as those used in Example 1), and otherwise under the same operating conditions as in Example 1. went. As a result, the cyclopentadiene conversion rate was 83 m.
Tetracyclododecene was obtained with an ol% and a tetracyclododecene selectivity of 66 mol%.

[0034]

INDUSTRIAL APPLICABILITY In the method for producing tetracyclododecenes according to the present invention, tetracyclododecenes can be produced more efficiently and very economically than the prior art.

[Brief description of drawings]

FIG. 1 is a schematic view of an apparatus used in the method for producing tetracyclododecenes of the present invention.

[Explanation of symbols]

1 Norbornene reservoir tank (may contain solvent) 2 Dicyclopentadiene reservoir tank 3 High boiling point substance reservoir tank 4 Olefin supply line 5 Mixer 6 Preheater 7 Reactor 8 First purification tower 9 Second purification tower

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshihiro Tate 6-1-2 Waki, Waki-cho, Kuga-gun, Yamaguchi Mitsui Petrochemical Industry Co., Ltd.

Claims (1)

[Claims] 1. (a) α-olefin, (b) cyclopentadiene or dicyclopentadiene, and (c)
Norbornene or a hydrocarbon group-substituted product thereof is heated and reacted in the presence of a high-boiling substance having a boiling point higher than that of tetracyclododecenes, wherein the high-boiling substance is (a),
A method for producing tetracyclododecenes, characterized in that the tetracyclododecenes are separated and recovered from a reaction product obtained by heating the components (b) and (c).